Method and apparatus for heating and quenching sucker rods



May 27, 1941.

E. E. STEVENSON METHOD AND APPARATUS FOR HEATING AND QUENCHING SUCKR RODS Filed May 1o,` 1958 [NVEN TOR.

I Patented May 27, 1,941

METHOD AND APPARATUS rolt HEATING QUENcmNG sUcKER nous Edward E. Stevenson, Los Angeles, alf., assignor to Ems'co Derrick & Equipment Company, Los Angeles, Calif., a corporation of California Application May 10, 1 938, Serial No. 207,027

e s claims. (ol. 14s-a1) My' invention relates to method and apparatus for heat treating a sucker rod.

In the oil pumping industry it is. common prac- `tice to employ a string of sucker rods forre ciprocating the pump plunger of the'pump which is located, usually, a considerable distance below the surface of the ground. The upper end of the string of sucker rods is connected by a polish rod to a reciprocating means whereby a're'cipro-l catory motion is transmitted to the pump plunger. During the operation of this apparatus the string of sucker rods is alternately subjected to tension and compression forces and, due to the weight of the long column of oil which is raised by the'pump plunger, severe stresses and strains are imposed on the sucker rods and serious consequences may-result in the event of sucker rod failure. v

The main object of my invention isto provide a method and an apparatus wherebya sucker rod may be heat treated to give it the desired physical properties, to produce a heat treated sucker rod which is straight and in which this may. accomplished with but a single heating of the. sucker rod. f

Another object of my invention is to provide a method and apparatus in which the sucker rod is heated to at least the transformation point, -then quenched at such a rate as' to produce a fine grained structure which is not brittle, and while simultaneously holding the sucker rodso that it vwill not warp during quenching operation. This enables the production of a straight sucker rod, which is 'fine grained, in a single heating and quenching operation.

It is a still further object of my invention to vprovide a method and apparatus in which the' pin and wrench engaging portion of the sucker rod is separately and simultaneously quenchedA in a suitable quenching medium, such as oil.

It is -a still further object of my invention to provide a method and apparatus in which the sucker rod is he'ld straight while the quenchingoperation is performed by the use of quenching dies which absorb the heat suiiici'ently rapidly to produce satisfactory physical qualities.

It is a still further object of my invention to provide a method'and apparatus for heat treating and quenching sucker rods in which a sucker rod ls held straight without placing a tension on for, and in which the quenching dies Withdraw the heat from the sucker rod and during such 4quenching operation-prevent warpage thereof.

It is found to be advantageous under certain conditions to oil quench the threaded pin andwrench receiving portion at the end of the sucker rod. It is, therefore, an object of my invention 'to provide .a method and apparatus in which,

during the quenching of the rod, the rod portion thereof maybe quenched by the quenching dies of myinvention, and the'end portion thereof may be quenched in oil.

-It is a still further object of my invention to provide an apparatus in which oil receptacles arejformed to receive the end portions of the rod during the quenching process and in which,

' if desired, means may be provided for intro- Referring to the drawing which is essentially' diagrammatic in character:

Fig. 1 is an elevational sectional view dia'- grammatically illustrating apparatus incorporating the features of my invention.

Fig. 2 is an enlarged fragmentary' sectional view looking in a downward direction at the end .of the quenching dies and at the receptacle formed at the end thereof for receiving the -end portion -of the sucker rod.

Fig. 3 is a fragmentary sectional view taken as indicated by the line 3-3 of Fig. 2, this view showing the position of the parts when the quenching dies .are engaged around the sucker rod.

Fig. 4 is a' fragmentary sectional view taken as indicated by the line 4--4 of Fig. 2 and showing the sucker rod and in which the. sucker rod is quenched while it is so held.

It is an 'object of my invention to provide a quenching apparatusfor quenching sucker rods which have been previously heated to at least the transformation point which includes metal quenching dies having channels to receive the .sucker rod, which quenching dies are movable into such a-position that the channels surround the sucker rod in order to form achamber therethe quenching dies in the positions they occupy when surrounding the sucker rod.

Fig. 5 is a fragmentary sectionalvi'e'w correl spending to Fig. 4 showing the position of the quenching dies when they are positioned to receive the sucker rod' tobe quenched thereby Fig. 6. is a fragmentary sectional vview corresponding to Fig. 4 but showing the position of the quenching dies when they have been separated so as'to allow a sucker rod which has been quenched thereby to fall therefrom for clearing the apparatus for receiving anothersucker rod for quenching.

Fig. 7 is an alternative form of my invention in which the cooling medium has direct contact with the rod.

Referring to the drawing in detail, the numeral Il represents a heat treating furnace which'may be of any-standard design or type capable of producing the necessary Atemperatures which are required in the heat treatment l 2,243,1 74- i UNIT-Ensures lPfrlazu'r oFF-ict:

of sucker rods. The heat treating furnace II has an inlet opening I2 and an outlet opening I4. Adapted to pass through the furnace II .is

an endless belt I having an engager I6. Sucker rods, as illustrated by the numerals I1, when placed on`the endless belt I5, may be pulled through the furnace II in a direction indicated by the arrow I3 at such speed as may be required to properly heat the sucker rod. As the sucker rod moves through the outlet opening I4 it is automatically delivered to an inclined-plate or chute which guides the sucker rod to the quenching means of my invention which is generally designated by the numeral 2|.

The quenching means of my invention includes a stationary jaw or stationary quenching die 22 and a movable jaw or movable quenching die 23. The quenching die 23 is connected to a piston rod 24 which extends through a, suitable supporting bearing 25 and which extends to a cylinder and piston arrangement including a cylinder 26 and a piston 21 operable therein and to which piston 21 the. rod 24 is connected. For moving the piston 21 in either direction as desired there is connected to the opposite. end of the cylinder 26 pipes 28 which are in turn connected to a four-way valve 29l which has an inlet pipe 30 and an outlet pipe 3|, which pipes are connected to a suitable meansfor supplying fluid under pressure and receiving fluid from the hydraulic system just described. By proper operation of the A four-way valve 29 the piston 21 may be moved in either direction and into'any position as desired. By controlling the four-way valve 23 the jaws may be closed in quenching position around a sucker rod, may be moved into discharge position so that the sucker rod may be discharged from the apparatus and may, in addition, be

a high temperature, such as is necessary in order to produce the desired physical changes therein, it ls, of course, of slightly larger diameter than after a quenching and it is necessary therefore to form the channels 35 with this fact'in consideration.

l In order that the quenching dies 22 and 23 may. have the ability tol extract the heat from the rod portion at a suitable rate of speedin order to produce the necessary quenching action these quenching dies may be provided with chambers .36 so. that a coolingI iiuid may be circulated therethrough at a suitable rate of speed being introduced and withdrawn from the chambers 38 V by suitable conduit means vsuch as indicated at 31.

One of the quenching dies, and preferably the movable quenching die 23, includes s rod support 33 which may be in the form of the series of rod supporting pins which are spaced along the length of the quenching die 23 at suitable distances. Each of the rod supporting pins is adapted to extend into holes 39 formed in the stationary quenching die 22 when the quenching dies are in quenching position vshown in Fig. 4. In Fig. 5 the quenching dies are shown in receiving position. It will be noted'that the rod supports moved into sucker rod receiving position so that a. sucker rod may be received from the chute 23 for quenching.

In Figs. 2 to 6 inclusive I have illustrated the details of the quenching means of my invention.

It will be understood that the sucker -rod, which is adapted to be heat treated and to be quenched by the apparatus of my invention and in accordance with my unique method, may be as long as thirty feet and may be from to one inch in diameter. The standard construction of a vsucker rod is that it includes a rod portion and at the end of the rod portion is what may be termed an end portion. This end portion is of larger diameter than the rod portion and includes a rectangular wrench receiving portion and a threaded pin whereby the same may be connected to a coupling. In the form of my invention illustrated hereinA the quenching dies 22 and 23 yare as long as the rod portion of the suckerrod I1 and are designed to hold the same fromwarping while they simultaneously extractthe heat therefrom in order to produce quench- `ing. The end portion of the suckerrod, in accordance with my present invention, may be subjectedduring this quenching operation to a separate quenching operation 'by being submerged in a suitable quenching fluid such as-oil are placed very lclose to the lower parts of the channels 35 so that when the rod is moved into a position between the quenching dies that thev same is held in a position so that when the jaws are closed the rod portion of the sucker rod will be received in the channels 35, as illustrated in Fig. 4.

In Fig. 6 I have illustrated the positions of the parts when it is desired to discharge the sucker rod from the apparatus. It will be seen at this time that there is sufficient space between the leftward end of the pin 38 and the stationary jaw 22 to permit the sucker'rod to pass downwardly and at this time the sucker rod may be received in a suitable bin such as illustrated at 40 in Fig. 1. f

' As shown best in Fig. 2, I have designated the rod portion of the sucker rod I1 by the numeral 43 and it will be seen that the end portions 44, including the wrench receiving portion and a threaded pin, project from the end of the quenching dies 22 and 23.' Secured to the ends of the quenching dies 22 and 23 are receptacle sections 45 which cooperate when the jaws are in closed position to form a receptacle 41. Inner end walls 48, lying against the end of the quenching dies or jaws 22 and 23, form a suitable seal to prevent fluid leakage at this' point. Each of the receptacle sections 46 have co-engaging faces 49,

which, when they meet, form a sufficiently tight seal to prevent uid leakage. One receptacle section may be provided with an inletconduit 50, another may be 'provided with an outlet conduit 5I whereby, at the desired time and in consequence of the manipulation of a suitable valve, a quenching fiuidsuch as oil, may be introduced through the conduit 5|! to fill the receptacle 41 and thus quench the end portion of the rod and may -thereafter be withdrawn through the outlet conduit 5I and lbefore the vquenching dies 22 and 23 are separated. When the quenchingv dies are separated the receptacle sections 46 yare Ispread aparta suilicient distance so that they will not interfere with the discharge of the sucker rod in a downward direction.

be snugly engaged. When the sucker rodis at 75 Having described the method and'apparatus -of my invention, I will now point out the sequence of operation.

Sucker rods to be subjected to the method of my invention are placed on the endless belt l and are carried through the heat treating furnace Il at the desired rate of speed. For sucker rods which are made of composition, including all SAE numbered steels, low carbon irons and wrought irons, plain and alloyed and copper nickel alloy steels up to 4% nickel and 2% copper content, I nd it satisfactory to raise the temperature thereof to between 1250 F. to 1850 F. for a period of approximately one to tWo hours.

Stating the temperature in another way in the heat treating furnace, the temperature of the sucker rod is raised to the transformation temperature or above.

As the heat treated sucker rod leaves the treating furnace Il 'it is discharged onto a chute 20 and is very quickly dropped onto 'a rod support pin and into the space between the quenching dies 22 and 23. At this time the quenching dies are in receiving position, as illustrated in Fig. 5. As soon as the sucker rod has reached this position the four-way valve 29 is manipulated in order to bring the quenching dies together into quenching position as illustrated in Fig. 4. This.move ment also brings the receptacle section 46 into the lposition shown in Figs. 2 and 3, so that the receptacle 41 is formed. When the dies are in this position, the surfaces of the channels 35 engage the outer cylindrical surface of the rod portion 43 and thus hold the same straight. At the same time heat is extracted from the rod portion at a iitable rate of speed by conduction and by thev flow of cooling liquid circulated through the quenching dies in order that the necessary cooling rate will be obtained to produce in the rod portion a fine grained structure with the desired toughness and physical properties. At this time, by the manipulation of a suitable valve, a quenching fluid 'is introduced into the receptacle 41 through the inlet conduit 50, Fthus filling the receptacle and quenching the end portion of the sucker rod. It is standard practice to use oil as a quenching medium, and this comes within the scope oi my invention. Before the movable quenching die 23 is moved in arightward direction the quenching fluid is withdrawn from the receptacle 4l through the outlet conduit 5I.

When this has been done the four-way valve is operated in order to move the movable quenching die 23 rightwardly so that the quenching dies occupy the relative positions as shown in Fig. 6. At this-time the sucker rod l1 is free to pass downwardly into the receiving bin 40, as shown in Fig. 1. The sucker rod to be treated and quenched, in accordance with my invention, has the necessary and desirable physical characteristics which adapt the sucker rod for the use to is to hom the sucker rbd in its normal straight Iposition and to act as a restraining means to prevent warpage should such tendency occur at any point along the rod. In other words, the rod is surrounded so that it cannot move radially' in any direction and this radial movement is prevented not by placing any tensile strains in the rod but by merely confining it so that it cannot move radially.

.In Figt 7 I show the die members 22 and 23 with openings, preferably staggered slots 10, for permitting the cooling medium to directly contact the rod l1.

It will, of course, be understood that my invention may be practiced without simultaneously quenching t-he end pontion of the sucker rod or by quenching the end portion in a different manner than that illustrated herein. It, will further be understood that different apparatus may be employed for practicing my invention so long as it incorporates the principle of the apparatus dis-` closed herein.

It is my invention, therefore, that this invention be not limited to the details illustrated herein but that the same be broadly construed in accordance with ,the spirit and scope of the appended claims.

I claim as my invention: l

.11. In an apparatus for quenching sucker rods which have been heated -to at least the trans,- formation point, the combination of: a plurality of quenching dies cooperating to form a chamber to receive the sucker rod with the ends thereof exposed; meansy for bringing the walls of said die members forming said chamber into pressural contact with the sucker rod; lwalls, supported by at least one of said quenching dies, forming a. receptacle at each end of the quenchends of the sucker rod; and means for introduc- .5 ing a quenching medium thereinto.

which it is put in the oil producing industry. Not

only does the structure haveV a ne grain but sumcient residual heat is left-m theV rod to tem-A per and toughen the steel; Furthermore, the rod i quenching operation and therefore a. better rod is produced :in a shorter period of time and at less.

cost.- It is an important feature of the invention that during the quenching operation the rod is not subjected to tension in order to keep it from warping. The action of the quenching dies 2. In an apparatus for quenching sucker rods which have been heatedvto at least the transformation point, the combination of: a plurality of quenching dies each having a. channel; means for circulating a cooling medium through said quenching dies; means for moving said quenching dies to cause said channels to surround said sucker rod in orderto absorb the heat therefrom and hold same straight; and receptacle forming means supported by said quenching dies and adapted to form a, quenching receptacle for receiving the end of said sucker rod when said quenching dies are in such a positionthat said channels surround said sucker' rod.

3. A method of heat treating a sucker rod which has a rod portion and a threaded end portion at each end of said rod portion, comprising: heating the sucker rod to at least the temperature of transformation; and quenching the sucker rod so as to obtain diierenlt degrees of hardness in said rod -portion and said end portions thereof. by simultaneously subjecting the rod portion and the end portions to, different conditions of quenching wherein metal quenching dies are brought into engagement with said rod portion and a. quenching of duid is brought into engagement with said end portions, so that heat will be extracted from said rod portion at a slower rate than the heat is extracted from said end portions.

EDWARD E. STEVENSON. 

